Originally Posted by Bill Cody
Good comments by FishinRod. In addition.
1. A smooth bottom is a sign of well compacted tightly sealed clay. Tracks in the bottom layer suggest, IMO just suggests, to me to indicate the clay was not well compacted. The smoother the bottom is IMO this means hard well compaction. Quality of compaction really depends on as FRod says moisture content of the clay and type of equipment used for compaction. Dozers and skid steers are not compaction machines, they are designed to float and not sink into the ground,. Good equipment operators should know this fact. stay dry the more they can dry out and then cracks form in the clay liner. When the cracks later water gets on top of them the crack is a crack and not a well mended together area as originally created & tight compacted. Cracks are not compacted when they fill with water and eventually lose sediment.
As Bill notes, some equipment (dozers, skidloaders) are made NOT to compact. However, if a pond has vibrating sheeps foot roller ( a great compacter) tracks on the bottom, that's a good thing. If the clay was compacted, something had to have done it, and I bet it left some kind of tracks.

"Live like you'll die tomorrow, but manage your grass like you'll live forever."
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